A pretend emerge shows two blocked packages.
What should I remove to be able to continue, and why
does this happen? (utemper and pam-login were needed in the past and I assume
are still in portage, yet portage now thinks it needs libutemper and shadow yet
these packages are incompatible. If removing utempter and pam-login from my
system is the answer, why can't portage do this as part of the ebuild process.....?)

"emerge -C utempter pam-login" then update the world. Make sure shadow gets updated before you reboot or else you won't be able to login. pam-login was merged into shadow I think, not sure why utempter needs to be uninstalled but I think it might be because whatever package that used utempter now uses libutempter and you can't have both installed at once.

As soon as I did the emerge -C
login no longer worked I can't log in on another window anymore.
su still works though.

After I do an emerge -uND system
what command do I need to use to update shadow so
logins will work again?

the emerge -uND should take care of updating shadow or you could just run emerge -u shadow

scharkalvin wrote:

And if the system should go down before the emerge finishes
how can I use the live cd to fix things?

just startup the livecd and mount the partitions to /mnt/gentoo and /mnt/gentoo/boot etc. Then chroot into is chroot /mnt/gentoo /bin/bash and run env-update and source /etc/profile then you are able to use your system almost as if you were running. Unfortunately if your internet does not work with the livecd you will have to use another computer to get the files and put them in /usr/portage/distfiles.